Soon after the Nintendo 3DS, photos surfaced of wrinkled 3DS buttons. The paint on the buttons and the Dpad seemed "warped".
The issue appeared isolated, but was related to the paint used on the 3DS. More photos have now surfaced showing how another 3DS had a warped D-pad that, over time, has started flaking and peeling.
Honestly, this could be a defective product. And I say this, not only as a 3DS owner, but as a 3DS owner who hasn't yet used his 3DS enough to cause the D-pad paint to fall off.